RFID (radio frequency identification) transponders, incorporated into inlays or tags include an antenna and an associated electronic microchip with memory for storing data which may be read (Read Only) and, in some configurations, memory for storing and changing data (Read/Write) on the microchip. RFID inlays may include a battery, in the case of an active RFID inlay or RF energy may be used to energize and interact with the microchip in the case of a passive RFID inlay. Radio frequency electrical energy is communicated to and from the microchip via the antenna, as is well known. Pre-assembled RFID inlays typically include an etched copper or aluminum antenna formed on a plastic film and are provided by suppliers such as Alien Technology, Morgan Hill, Calif., Omron Electronics of Tokyo, Japan, Texas Instruments of Plano, Tex., and Rafsec of Tampere, Finland. Printed antennas may also be used in pre-assembled RFID inlays.
Preassembled RFID inlays may be applied between conventional label facestock and liner to provide an RFID label. The process of placing an RFID inlay between facestock and liner is often called inserting. Inserting may be accomplished by delaminating (i.e. separating) label facestock and liner, applying or inserting the RFID inlay on the exposed adhesive side of the facestock and then relaminating the facestock/inlay combination with the liner. Equipment for inserting RFID inlays is available from Melzer GmbH of Schwelm, Germany or Tamarack Products of Wauconda, Ill. U.S. Pat. No. 6,019,865 of Palmer et al. and U.S. Pat. No. 6,451,154 of Grabau et al. describe, among other things, processes for applying adhesive and release coatings to make label stock in situ and inserting RFID inlays (or simply, “inlays”) to make RFID labels both with and without liner.
As used herein, an “inlay” comprises an RFID microchip electronically coupled to an associated antenna. The chip may be directly attached to the antenna, or it may be attached using intermediate conductive pads to facilitate the connection, as discussed further below. In general, a roll of unseparated inlays forming an inlay web is unwound and fed to a rotating cutting cylinder which cuts individual inlays in register with the antenna/chip pattern or repeat (to avoid cutting the antenna or damaging the chip) to provide individual or singulated inlays. The singulated inlays are carried on a rotating vacuum cylinder (which cooperates with the cutting cylinder to complete the cut) and brought into contact with adhesive on one side of the label face stock. In an alternative process, the singulated inlays may be joined to the release liner with either an adhesive on one side of the inlay (an inlay carrying an adhesive is sometimes referred to as a “wet” inlay) or an adhesive on at least the portion of liner in register with an inlay.
RFID straps are relatively small (approximately 5 mm×10 mm when viewed from above) intermediate components or units that may be used in the manufacture of RFID inlays, transponders or other devices. RFID straps typically include a film substrate such as PET (polyethylene terephthalate) polyester or Kapton (polyamide) which includes a microchip attached to electrically conductive pads. The strap is then attached to a printed, etched, foil-stamped, or fine wire antenna to form an RFID inlay or an RFID article such as a label, transponder, or tag. RFID straps are provided by suppliers such as Alien Technologies of Morgan Hill, Ca, and Texas Instruments of Plano, Tex.
An RFID strap at approximately 5 mm×10 mm, while relatively small, is nevertheless considerably easier to handle and apply than much smaller microchips at approximately 0.75 mm square or smaller. An RFID microchip is typically applied in controlled environments by precision pick-and-place devices such as provided by Universal Instruments Corporation of Binghamton, N.Y. or Mühlbauer AG High Tech International of Roding, Germany. RFID straps, however, may be attached to associated antennas with less precise equipment in a less ‘clean’ environment than attaching the chips directly to antennas. Compared to pre-assembled, inserted RFID inlays, the combination of (i) an RFID antenna printed with conductive ink directly on a paper or plastic label facestock, or directly on a cartonboard or corrugated stock and (ii) an RFID strap may allow significant cost savings and greater flexibility in customizing antennas for specific purposes.
For many years, an applicator apparatus known as the Tamarack Label Applicator described in U.S. Pat. No. 6,207,001 has been used to cut a piece of material, known as a patch, from a strap web, known as the patch web and apply it to another web of material, known as the carrier web. This applicator has been used to make business forms with integral labels (for example, the integral label of U.S. Pat. No. 4,379,573 of Lomeli et al.) and integral cards and to apply RFID inlays to business forms and label webs. It would be desirable to have an apparatus similar to current vacuum cylinder applicators such as that supplied by Tamarack Products to apply both RFID inlays and RFID straps. With servo-driven feeding, cutting, and vacuum cylinder axes, such vacuum cylinder control systems provide convenience, accuracy and control for handling a wide variety of materials, cut widths, cut lengths and applied pitch or repeat.
The typical geometry of the vacuum cylinder applicator, however, causes a problem when cutting a strap web into individual straps due to both the relatively small cut length (approx. 5 mm) combined with the height of the microchip above the strap carrier film (approx. 0.3 mm). The problem is that the cutting blade sweeps through the space occupied by the microchip. This can destroy the microchip and/or push the strap web ahead causing the cut to occur at a location on the straps other than the desired cut position (d.c.p.).